My first attempt at an e bike.
 

I got the idea yesterday to build an electric bike so i did a little research. Today, after an hour of light construction, I had successfully taken v 1.0 out for my first ride. Cost: zero dollars. I built this version out of junk i had laying around.

Here is a short youtube video of the insanity here:


http://www.skoolie.net/gallery/d/38385-2/108.JPG

http://www.skoolie.net/gallery/d/38388-2/110.JPG

Motor: Although i have a couple of 400 watt e scooter motors i bought a few years back, i decided to not use them. Instead I chose to use a motor out of a junk treadmill. It's rated for 130 vdc.

Drive: Friction, using the already installed metal flywheel on the motor

Speed controller: None, just using an on/off switch that currently isn't very accessible. Remember, safety third!

Battery: First i used electric drill batteries. With 18 volts, i counted the revs of the bike tire and calculated about 18 mph no load. I rode a little ways on 18 volts and decided that wasn't quite enough oomph. So i put 2 of them in series for 36 volts. This is a nearly perfect amount of speed and power. Unfortunately I only have 2 batteries, and they are different brands. Also, they are several years old and near the end of their life expectancy. On a full charge, i was able to travel about 3 miles. I don't have a speedo, and did not yet get out my gps. The bike travels at the upper end of what i am comfortably able to pedal in high gear. I assisted the bike for the 3 miles i traveled.


While those batteries were charging, i decided to see what would happen with just a plain ol 12 volt lead acid car battery i had laying around. I thought maybe the motor would run good on 12 volts since the battery could deliver hundreds of amps if necessary (although not realistic with the small wires the motor uses) It turns out that 12 volts is too slow and wimpy. I did what any backyard hillbilly would do....I added a second battery. I realize that full size auto batteries are not practical on a bicycle, I also realize that starting batteries are not meant to be used for deep cycle applications. This is really just a learning exercise to see how the bike works with different voltages. They aren't even the same type, age, brand, or size.

I rode for about 40 minutes, letting the motor do most of the work. Performance was definitely lacking with only 24 volts. At least 36 is a must. I do have a 3rd automotive battery i could utilize, but i lack the desire to attach it to the bike. The motor got a little warm, but never hot to the touch, even after 40 minutes of riding.

http://www.skoolie.net/gallery/d/38391-2/118.JPG

http://www.skoolie.net/gallery/d/38394-2/120.JPG

I think that three smaller sized 12 volt sla batteries are going to be my plans for the future......although, if 36 is good, maybe 48 volts will be better!

Also, the knobby tire is not the most desirable for friction drive, but it's what i had on hand. Where do we go from here? I dont' know....I was very happy with how things worked out, especially since i spent such a small amount of time on the project.

If i had all the money in the world, i would like to use li-ion batteries. Unfortunately, i don't have the desire to throw that kind of money at this project.

Good for you!

It looks like it weighs a ton though! :)

Put those batteries on a trailer.

1. amazing project
2. I can't believe you have lived to your current age without exploding

I love how everyone says "I made it for free (out if parts lying around)". That's not exactly "free". Those parts came from something you bought at some time.....
UNLESS, you found EVERY part in the garbage or wad given to you for nothing.

Yeah, but if it is built out of stuff that is just laying around, and doesn't require any money to put it together, that's pretty much free.

The bike was free
I did buy a treadmill from craigslist some time ago for $25 and planned to use it for another project, but never got around to it.
One battery i got for free
The other battery was out of my 3rd vehicle, which is sitting out in a field
The drill batteries are used for my drills. The Milwaukee was free, I got the dewalt as a present many years ago.
I did buy welding rod a couple years ago, and i'm sure i had to pay for the electricity.
The scrap metal i had laying around, same goes for the wire and switch.

i got my car for free. i bought it a few years ago but it was just sitting in my garage so i felt like using it.

lol, yeah i'm a smart ass. nice build for cheap parts...probably around $200 worth of parts. you might want to get a lighter (and safer) battery setup, etc.

nothing wrong with experimentation....and learning new things....

but most people will tell you if you already have a bicycle you like, its usually much better to buy a complete brishless hub kit and install it, then rig up a homemade kit using cheap components that will be inefficient and heavy in weight...

in other words, if you are serious about wanting a ebike, you could buy a complete front mount brushless hub kit , with battery/s , for around $400 - $ 750 and you would have a much more reliable, faster setup that will also go alot farther then the homemade 12 volt battery setups , in which you have to lug around a lead acid battery that weighs up to 40 lbs.....and thats only for a 12 volt system...

the current technology and low price point of premade brushless hub kits, almost make it totally absurd to try and build home kits out of weak brushess motors , friction drive systems and heavy 12 volt batterys.

I think there can be lots of benefits to experimenting like this. I bet you learned something! :)

Making your own ebike ensures you know how to fix it. You also know a few things to do differently next time and what components may be worth more of an investment...

Ebikes make life just a little bit easier
 

Wow! that's absolutely fantastic (and hilarious) :-)

I'm from Denmark, and here ebikes aren't that popular. Many guys don't see themselves riding ebikes because they feel imasculinated. Many people laugh at people riding ebikes because they think it's sissy. I on the other hand think it's great for the ones who ignore this. The launch of ebikes on the market has resulted in many people, who normally wouldn't ride a bike, have begun riding these helpful machines. Ebikes don't do it all for you, but rather help speed up things. It's better to ride an ebike than not to ride at all.

My friend is quite overweight, and he just purchased an ebike on the net at Coops webshop (category: Cykler).

A few years ago ebikes weighed about as much as a scooter and cost twice as much, but today the ebikes have improved considerably. The quality, distance, weight and price has really made it interesting to acquire an ebike. I'm deifnetly considering to get one, for longer journeys.

Diy is the most fun
 

nothing wrong with using your brain and having a tinker. I converted two bikes with this system for £110-£130 each just to get a feel for electric assist. One did over 20 miles (24ah 24v 14 pounds sla) one did over 10 miles (10ah 24v 7pounds sla). The front of this one for my mrs runs a sturmy three speed hub for 14 19 and 22mph modes. Good luck stopping it at 22mph lol They have been going for around 500 miles without issue and love the fact it has a freewheel so you arnt pushing a hub motor if the battery packs up etc.http://i1239.photobucket.com/albums/...6032011087.jpg

I give you guys credit for experimenting and building your own. Quite resourceful! I'vw wondered about using deep cycle marine batteries. I've used them with trolling/fishing motors and as a power source for lights in a detached garage.